1. Field of the Invention
This invention relates to safety guards to protect against needle stick injuries used in medical and veterinary medical use of material delivery and material removal needles.
2. Background of the Art
According to the Occupational Safety and Health Administration (OSHA), needle stick injuries occur during all aspects of handling. 50% of incidents occur during the invasive procedure (while introducing needle, by accidental needle withdrawal during procedure, or during needle withdrawal at the end of the procedure).
Ironically, the vast majority of safety needle devices currently on the market only give protection to the healthcare worker after completion of the invasive procedure.
Examples of disclosures of safety devices which protect needles by moving a protective shield over the sharp end of the needle are bountiful. Most of the disclosures describe a technique where the needle tip is exposed by first removing a protective cap and where the protective shield is moved form a collapsed position proximal to the user to a distal and extended position to cover the needle tip only after the invasive procedure has been completed.
U.S. Pat. No. 9,005,232 (KIM) discloses a lancing system comprising a lancet with a handle portion and a needle bearing portion, the needle bearing portion retaining a thin needle protected by a safety cap. The safety cap includes first and second chambers, where the first chamber acts as a sheath and the second chamber having a surface positioned to compromise the structure of the needle when the needle bearing portion of the lancet body is inserted into the second chamber.
U.S. Pat. No. 7,361,159 (Fiser) describes a safety apparatus is provided which includes a needle hub having an arm extending therefrom and an extensible frame connected to the needle hub. The extensible frame includes a proximal segment that is hingedly connected to a distal segment. The extensible frame is resiliently biased from a retracted position to an extended position, wherein the arm releasably engages the proximal segment to fix the extensible frame in a position between the retracted position and the extended position. In an alternate embodiment, the safety apparatus includes an extensible frame including a proximal segment which is hingedly connected to a distal segment. A resilient member is coupled to the proximal segment and the distal segment. The resilient member is configured to bias the extensible frame from a retracted position to an extended position. A method for infusing fluids to a subject is disclosed.
U.S. Pat. No. 7,534,232 (Iwase) discloses an indwelling needle composed of a body having a closed end, a needle forming at the tip a sharp edge, a tubular hub retaining the proximal end of the needle and slideable along the main body, a protective cover slidable along the main body and projecting from the main body, and a spring elastically fitted between the body and the protective cover. When a first projection is lifted by actuating a lever provided on the body and retractable along with the protective cover relative to the body, the first projection is housed in a through hole and presses a second projection of the protective cover engaged with a second engaging portion toward the inner circumference, rendering an operative state. The resultant length of indwelling needle in operative state can be modified, inhibiting injury to patient. U.S. Pat. No. 7,090,656 describes a hypodermic injection system with a retractable needle wherein the needle retracts within an interior cavity of a syringe plunger, such that the needle is confined within the plunger. A spring biases the needle rearwardly into the plunger, and a needle retainer releasably retains the needle against the bias of the spring. The plunger has a frangible end, which dissociates when the plunger engages the needle retainer, allowing the coiled spring to eject the needle into the interior cavity of the plunger. A body fluid sampling embodiment employs the same functional elements except the plunger is shorter and contains a linking that communicates with a vacuum container. The container allows fluid sampling and provides the structure to release the spring retracting the needle. The retractable needle embodiment is also employed with an insertion needle that guides a catheter tube below the skin of a patient and into the vein, and allows retraction of the insertion needle thereby avoiding accidental pricking of the health care worker by the insertion needle.
U.S. Pat. No. 5,634,909 (Schmitz) discloses a hypodermic injection system utilizes disposable medicament ampules having self-contained needles operated by a re-useable actuator to extend the needle from complete enclosure within the ampule out and into the flesh and inject the medicament as it moves, the needle automatically retracting into the disposable ampule after exhausting its contents, completely eliminating any need to handle the exposed needle before or after use.
U.S. Pat. Nos. 5,188,599 and 4,994,034 (Botich) disclose a hypodermic injection system (7) with a retractable needle (9) wherein the needle (9) retracts within an interior cavity (71) of a syringe plunger (59), such that the needle (9) is confinedly held within the plunger (59). A cylindrical spring housing (21) has resilient fingers (23) which captures a spring (15) biasly holding a needle holder (11) against the retaining force of resilient fingers (23). The plunger (59) has a frangible end (65), which dissociates when the outwardly tapered shoulders (68) spread the resilient fingers (23), allowing the coiled spring (15) to eject the needle (9) and its holder (11) into the interior cavity (71) of the syringe plunger (59). A body fluid sampling embodiment employs the same functional elements except the plunger (59″) is shorter and contains a linking needle (137) that communicates with a vacuum container (147). The container allows fluid sampling and provides the structure to release the spring (15″) retracting the needle (9″).
U.S. Pat. No. 4,955,866 (Corey) provides a recapping device for use with medical devices including all hollow and solid medical needles of the type used for entry into the body and into closed intravenous and intraarterial systems for access, sampling, and injection of medications, and are withdrawn after use. The recapping device includes a hollow sleeve encircling a portion of the needle and having a distal end aperture adapted to permit the sleeve to slide between a first position on the medical device wherein the needle is exposed to enable use of the needle, and a second position characterized by the distal end of the needle being contained within the distal end capped hollow sleeve, and the device may optionally contain a housing for a free-floating fenestrated disk, which, upon movement of the device to its second position wherein the tip of the needle exits the distal end aperture, shifts position to provide an obstruction at that aperture. A securing means for the hollow sleeve, such as a tether, is provided for permitting substantially free slidable movement of the hollow sleeve between the first and second positions.
US Published Patent Application Nos. 20080132838 20100100039 20110226646 (Wyrick) disclose a reloadable medicine injector and methods are described in which a barrel with a receiving cavity is adapted to slidably receive a syringe subassembly for axial movement therein. Upon removal of a safety and release of a syringe driver, the syringe driver moves forward and injects the syringe needle. A plurality of penetration controls are shown for controlling injection needle penetration depth. The penetration controls have an abutment and various lengths to provide different needle penetration depth positions. In one form of penetration control a sleeve is used against which the syringe or related parts contact. In another form the front return spring is used as a penetration control. A cushioning ring may be used to reduce syringe breakage. A load distribution and guide ring may be used to distribute loading applied to the syringe and help guide the moving syringe.
US Published Patent Application No. 20070078409 (Salyz) escribes a protective needle guard assembly features a hub that is removably secured to a reusable syringes, a first and a second needle extending outwardly from the hub in opposite directions, and a moveable sheath that moves about an outer surface of the syringe. The needle guard includes an engagement device that engages the moveable sheath to secure the moveable sheath in an extended position wherein the moveable sheath extends beyond the distal end of the first needle. The moveable sheath features a retracted position wherein the first needle is substantially exposed. A cavity formed in the hub substantially covers and protects the second needle.
Other relevant disclosures are included in U.S. Pat. Nos. 5,348,544; 5,910,130; 5,256,152; 4,935,013; 4,735,618; 5,250,031; 5,295,972; and 5,584,818; and US20110066107; and EP0 654281. Most of the disclosures describe a way of blocking the needle path by means of a metallic clip or rotating member located in the distal needle cap and this only after the invasive procedure has been completed. These disclosures still are not believed to offers high levels of security and additional advances are still needed. These disclosures are incorporated herein by reference in their entirety by reference.